com.vividsolutions.jts.index.strtree
Class AbstractSTRtree

java.lang.Object
  com.vividsolutions.jts.index.strtree.AbstractSTRtree

Direct Known Subclasses:

SIRtree, STRtree

public abstract class AbstractSTRtree
extends java.lang.Object

Base class for STRtree and SIRtree. STR-packed R-trees are described in: P. Rigaux, Michel Scholl and Agnes Voisard. Spatial Databases With Application To GIS. Morgan Kaufmann, San Francisco, 2002.

This implementation is based on Boundables rather than just AbstractNodes, because the STR algorithm operates on both nodes and data, both of which are treated here as Boundables.

Version:

1.7

See Also:

STRtree, SIRtree

Nested Class Summary

protected static interface

AbstractSTRtree.IntersectsOp A test for intersection between two bounds, necessary because subclasses of AbstractSTRtree have different implementations of bounds.

Field Summary

protected AbstractNode

root

Constructor Summary

AbstractSTRtree(int nodeCapacity)
Constructs an AbstractSTRtree with the specified maximum number of child nodes that a node may have

Method Summary

protected java.util.List	boundablesAtLevel(int level)
void	build() Creates parent nodes, grandparent nodes, and so forth up to the root node, for the data that has been inserted into the tree.
protected int	compareDoubles(double a, double b)
protected abstract AbstractNode	createNode(int level)
protected java.util.List	createParentBoundables(java.util.List childBoundables, int newLevel) Sorts the childBoundables then divides them into groups of size M, where M is the node capacity.
protected int	depth()
protected int	depth(AbstractNode node)
protected abstract java.util.Comparator	getComparator()
protected abstract AbstractSTRtree.IntersectsOp	getIntersectsOp()
int	getNodeCapacity() Returns the maximum number of child nodes that a node may have
AbstractNode	getRoot()
protected void	insert(java.lang.Object bounds, java.lang.Object item)
java.util.List	itemsTree() Gets a tree structure (as a nested list) corresponding to the structure of the items and nodes in this tree.
protected AbstractNode	lastNode(java.util.List nodes)
protected java.util.List	query(java.lang.Object searchBounds) Also builds the tree, if necessary.
protected void	query(java.lang.Object searchBounds, ItemVisitor visitor) Also builds the tree, if necessary.
protected boolean	remove(java.lang.Object searchBounds, java.lang.Object item) Removes an item from the tree.
protected int	size()
protected int	size(AbstractNode node)

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

root

protected AbstractNode root

Constructor Detail

AbstractSTRtree

public AbstractSTRtree(int nodeCapacity)

Constructs an AbstractSTRtree with the specified maximum number of child nodes that a node may have

Method Detail

build

public void build()

Creates parent nodes, grandparent nodes, and so forth up to the root node, for the data that has been inserted into the tree. Can only be called once, and thus can be called only after all of the data has been inserted into the tree.

createNode

protected abstract AbstractNode createNode(int level)

createParentBoundables

protected java.util.List createParentBoundables(java.util.List childBoundables,
                                                int newLevel)

Sorts the childBoundables then divides them into groups of size M, where M is the node capacity.

lastNode

protected AbstractNode lastNode(java.util.List nodes)

compareDoubles

protected int compareDoubles(double a,
                             double b)

getRoot

public AbstractNode getRoot()

getNodeCapacity

public int getNodeCapacity()

Returns the maximum number of child nodes that a node may have

size

protected int size()

size

protected int size(AbstractNode node)

depth

protected int depth()

depth

protected int depth(AbstractNode node)

insert

protected void insert(java.lang.Object bounds,
                      java.lang.Object item)

query

protected java.util.List query(java.lang.Object searchBounds)

Also builds the tree, if necessary.

query

protected void query(java.lang.Object searchBounds,
                     ItemVisitor visitor)

Also builds the tree, if necessary.

getIntersectsOp

protected abstract AbstractSTRtree.IntersectsOp getIntersectsOp()

Returns:

a test for intersection between two bounds, necessary because subclasses of AbstractSTRtree have different implementations of bounds.

See Also:

AbstractSTRtree.IntersectsOp

itemsTree

public java.util.List itemsTree()

Gets a tree structure (as a nested list) corresponding to the structure of the items and nodes in this tree.

The returned Lists contain either Object items, or Lists which correspond to subtrees of the tree Subtrees which do not contain any items are not included.

Builds the tree if necessary.

Returns:

a List of items and/or Lists

remove

protected boolean remove(java.lang.Object searchBounds,
                         java.lang.Object item)

Removes an item from the tree. (Builds the tree, if necessary.)

boundablesAtLevel

protected java.util.List boundablesAtLevel(int level)

getComparator

protected abstract java.util.Comparator getComparator()